books

Books about Erfle:

booksManagerial Economics (7th Edition) 7th (seventh) by Keat, Paul, Young, Philip K, Erfle, Steve (2013) Hardcover... (2013)

booksManagerial Economics (7th Edition) by Keat, Paul, Young, Philip K, Erfle, Steve (2013) Hardcover by Paul, Young, Philip K, Erfle, Steve Keat (1011)

booksAstronomy January 1980 Alien Eyes What Good is an Erfle Observing Mars by Astronomy (1980)

wiki

Wiki information Erfle:

Heinrich Erfle
Inventor, Deceased Person, Person

Heinrich Erfle was a German optician who spent most of his career at Carl Zeiss. In 1917 he invented the first wide-field eyepieces for telescopes and binoculars. During his short life he developed a number of new designs for telescopes and...

Tiefland: Aufz. II. "Ich will von Himmel Stärke dir erflehn" (Tommaso)
Musical Recording, Canonical Version